Autologous haemopoietic stem-cell transplantation followed by allogeneic or autologous haemopoietic stem-cell transplantation in patients with multiple myeloma (BMT CTN 0102): a phase 3 biological assignment trial.

BACKGROUND: Autologous haemopoietic stem-cell transplantation (HSCT) improves survival in patients with multiple myeloma, but disease progression remains an issue. Allogeneic HSCT might reduce disease progression, but can be associated with high treatment-related mortality. Thus, we aimed to assess effectiveness of allogeneic HSCT with non-myeloablative conditioning after autologous HSCT compared with tandem autologous HSCT.

METHODS: In our phase 3 biological assignment trial, we enrolled patients with multiple myeloma attending 37 transplant centres in the USA. Patients (

FINDINGS: Between Dec 17, 2003, and March 30, 2007, we enrolled 710 patients, of whom 625 had standard-risk disease and received an autologous HSCT. 156 (83%) of 189 patients with standard-risk disease in the auto-allo group and 366 (84%) of 436 in the auto-auto group received a second transplant. 219 patients in the auto-auto group were randomly assigned to observation and 217 to receive maintenance treatment, of whom 168 (77%) completed this treatment. PFS and overall survival did not differ between maintenance and observation groups and pooled data were used. Kaplan-Meier estimates of 3-year PFS were 43% (95% CI 36-51) in the auto-allo group and 46% (42-51) in the auto-auto group (p=0·671); overall survival also did not differ at 3 years (77% [95% CI 72-84] vs 80% [77-84]; p=0·191). Within 3 years, 87 (46%) of 189 patients in the auto-allo group had grade 3-5 adverse events as did 185 (42%) of 436 patients in the auto-auto group. The adverse events that differed most between groups were hyperbilirubinaemia (21 [11%] patients in the auto-allo group vs 14 [3%] in the auto-auto group) and peripheral neuropathy (11 [6%] in the auto-allo group vs 52 [12%] in the auto-auto group).

INTERPRETATION: Non-myeloablative allogeneic HSCT after autologous HSCT is not more effective than tandem autologous HSCT for patients with standard-risk multiple myeloma. Further enhancement of the graft versus myeloma effect and reduction in transplant-related mortality are needed to improve the allogeneic HSCT approach.

FUNDING: US National Heart, Lung, and Blood Institute and the National Cancer Institute.